The Research Methods Core, following the principal goals of the CIDAR Program Announcement, aims to[unreadable] foster fuller integration of innovative basic research methods into the clinical assessment and therapeutics[unreadable] arena. Supporting each of the 4 research projects and advancing the overall goals of the CIDAR, the RMC[unreadable] has 3 specific aims comprising both service and scientific missions: Specific Aim 1: Implement cognitive and[unreadable] neurophysiological assessment methods across projects, guaranteeing uniformity and high quality in data[unreadable] collection, recording, and analysis; Specific Aim 2: Collect data on a reference sample of healthy volunteers[unreadable] matched to the combined demographic characteristics of projects I and IV (thereby also matching project III);[unreadable] and Specific Aim 3: Further refine measures using psychometric methods and modeling, and combining[unreadable] information across projects, to inform the development pipeline for novel assays and biomarkers of cognitive[unreadable] control that will be useful for future therapeutic trials and translational research. Assay refinement will rely on[unreadable] determinations of: (a) discriminant validity (with respect to the diagnosis of ADHD); (b) construct (nomothetic)[unreadable] validity for combinations of indicators; (c) concurrent validity with respect to neural systems effect; and (d) exploratory cross-validation with respect to treatment effects. The RMC is staffed by a team of experts in neurocognitive assessment,[unreadable] neurophysiological assessment, psychometrics and measurement methods, with extensive experience[unreadable] specifically in the implementation of cognitive and neurophysiological service core functions in NIMH[unreadable] Centers, and in the scientific integration of high-dimensional, multimodal data sources to enable inferences[unreadable] about underlying neural systems processes affected in cognitive control disorders. The long-term aims of[unreadable] the RMC include development and deployment of integrated "panels" of behavioral and neurophysiological[unreadable] assays, cross-validated in translational research, which can be used in clinical trials of next-generation[unreadable] psychopharmacological and behavioral interventions for pediatric disorders of cognitive control. The RMC[unreadable] will also disseminate these novel assays and analysis methods freely to the scientific community.